Sept. 12, 2012 -- New guidelines highlight two key recommendations about
strep throat: Recurring cases should not necessarily lead to having tonsils removed. And overdiagnosis of strep needs to be reined in, because it's a major contributor to antibiotic overuse and resistance in the U.S.

In the new guidelines released this week, the Infectious Disease Society of America (IDSA) called on doctors to be selective about who they test for strep throat, and to confirm a suspected diagnosis before prescribing antibiotics.

The doctors group also recommends against removing a child's tonsils just because they've had multiple cases of strep over the course of one year.

Americans make about 15 million doctor visits for sore throats each year. But only a small percentage of these patients actually have strep throat, a bacterial infection that responds to treatment with antibiotics.

The rest -- as many as 80% of children and 95% of adults -- have sore throats caused by viral infections (such as the common cold) that are not helped by the drugs.

Cough and Runny Nose? It's Not Strep

The guidelines state that people with obvious cold symptoms such as runny nose, cough, hoarseness, and mouth sores, do not need to be tested for strep throat.

A sore throat that comes on suddenly with fever, but without these cold symptoms, is far more likely to be strep.

When strep throat is suspected, the diagnosis can often be confirmed in just a few minutes with a rapid strep test.

If the rapid strep test doesn't confirm a strep infection, a throat culture is recommended for children over the age of 3 and for teens, but not for most adults. (The culture involves another swab of the throat that is sent to the lab to see if strep bacteria grow. This test takes longer for results.)

There is almost no risk that strep throat in very young children and adults will lead to rheumatic fever, an increasingly rare but potentially deadly complication.

Although the rheumatic fever risk is small in older children and teens, it is still important to identify and treat strep throat in this age group to lower the risk even further, says researcher Stanford T. Shulman, MD, chief of the division of infectious disease at Ann & Robert H. Lurie Children's Hospital of Chicago.

Most Kids Don't Benefit From Tonsil Surgery

The revised guidelines recommend against surgery to remove the tonsils of children with recurring sore throats, unless they have complicating symptoms such as obstructed breathing.

Many doctors have recommended tonsillectomy for repeated strep throat infections.

But studies show that tonsillectomies benefit a very small group of people, and these benefits tend to be short-lived, Shulman says.

When strep throat is confirmed and treatment is indicated, the new guidelines call for treating patients with a 10-day course of either penicillin or amoxicillin.

Shulman says these old-school antibiotics are less likely to promote resistance and are a better choice, at least for patients who are not allergic to them. If patients are allergic to them, doctors can prescribe other antibiotics instead.

Ear, nose, and throat specialist Monica Okun, MD, of Lenox Hill Hospital in New York, says many patients still expect to go home with a prescription for antibiotics when they go to the doctor with a sore throat, even though most do not benefit from them.

"Every year we see new studies showing the dangers of antibiotic overuse," she says. "The message is getting out to physicians and patients, but these drugs are still widely overprescribed."

The new guidelines appear in the October issue of the journal Clinical Infectious Diseases.